It is often necessary to drill an array of spaced apart bores into the walls of a building or the like for the purpose of fastening additional material to the wall. The additional material may variously be slabs, panels or slats of outer or interior facing material, poured concrete, shot crete or a number of other structural materials. The bores receive the bolts, studs, screws, reinforcing steel rods or the like which anchor the facinq material to the wall.
Manual drilling of such an array of bores on a one by one basis, using a hand held motorized drill, can be costly, time consuming and tedious particularly in connection with the construction or rehabilitation of sizable buildings. This procedure may also result in mislocated bores or bores that do not have a precisely uniform spacing that may be needed when preformed slabs with fixed anchors are to be fastened to the wall.
It would be advantageous if groups of such bores could be drilled concurrently and with a precisely fixed spacing with respect to each other. Drilling mechanisms have heretofore been devised which have a plurality of drill bits that operate simultaneously to drill plural passages but these do not have the characteristics that are needed for drilling arrays of bores in vertical surfaces such as a building wall.
Many such prior ganged drill mechanisms are fixed installations for use in factories and are adapted only for drilling into successive workpieces that must be traveled through the mechanism. Other mechanisms of this general type are designed for tunneling or mining and have arrays of projecting drills carried on apparatus which progresses along the route of the shaft. Drilling of arrays of bores in building walls requires a type of mobility and forms of adjustability in drill positions and spacing that are not provided by such prior mechanisms.
The present invention is directed to overcoming one or more of the problems discussed above.